Medical Policy: 07.01.62 
Original Effective Date: January 2014 
Reviewed: October 2015 
Revised: October 2015 

Benefit Application:

Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.

This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.


Gastric Electrical Stimulation

Gastric electrical stimulation (GES) is performed to treat chronic, intractable nausea and vomiting secondary to gastroparesis of diabetic, idiopathic, or postsurgical etiology. Gastric electrical stimulation/pacing has also been investigated as a treatment of obesity. The device may also be referred to as a gastric pacemaker.


Gastric electrical stimulation uses an implantable electric stimulator that helps control the chronic nausea and vomiting associated with gastroparesis by stimulating the smooth muscles of the lower stomach. A small, battery powered gastric neurostimulator is implanted beneath the skin in the lower abdominal region. Leads deliver mild, controlled electrical pulses to the antrum portion of the stomach muscle wall.


The effect of the high frequency/low energy pacing on gastric contractility is unclear, as is the mechanism of action in decreasing symptomology. It has been hypothesized that the symptomatic improvement that has been observed is caused by modulation of enteric or afferent neural activity that influences symptom perception or that influences a central nausea and vomiting control mechanism. Also, there has been recent reports that indicate that GES therapy changes various electrogastrography parameters, fundic relaxation, the autonomic nervous system and gastrointestinal hormone levels. These processes may play some role in the effect of GES. 


Gastroparesis is defined as delayed gastric emptying of solids in the absence of mechanical obstruction. It can frequently result from longstanding diabetes mellitus and vagal nerve injury, or can be idiopathic in nature. Gastroparesis leads to postprandial nausea and vomiting, bloating, early satiety and discomfort. In severe cases, nausea and vomiting may cause weight loss, dehydration, electrolyte disturbances and malnutrition due to inadequate caloric and fluid intake. 

Primary medical management for gastroparesis includes dietary modification and pharmacologic therapy with prokinetic (metoclopramide and erythromycin) and antiemetic agents. Patients refractory to treatment are difficult to manage. Treatment may involve changing or combining medications; placement of gastrostomy or jejunostomy tube for enteral feedings, or in severe cases, total parenteral nutrition (TPN) for brief periods. Some patients, however, remain refractory to gastroparesis treatment. 


Currently, only one gastric electrical stimulator has received approval from the U.S. Food and Drug Administration (FDA), the Enterra™ Therapy System, manufactured by Medtronic and it was cleared by the FDA as a humanitarian use device. This system delivers a high frequency (12 cycles per minute), low energy stimulation to the stomach.  The FDA labeling for Enterra™ Therapy System indicates the use of this system for the treatment of chronic, intractable (drug refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology.


Gastric Pacing
Gastric pacing (gastric pacemaker) entails the use of a set of pacing wires attached to the stomach and an external electrical device that provides a low frequency, high energy stimulation to entrain the stomach at a rhythm of 3 cycles per minute. However, the gastric pacemaker is cumbersome and problematic for chronic use because of external leads.


Obesity is a major health problem among adults in the United States. It is also an increasing health concern among American children as well as adolescents. Various methods are employed in the management of obesity. One of the new approaches is gastric pacing, which is intended to induce early satiety through electrical stimulation of the gastric wall. However, the effectiveness of this technique in the treatment of obesity has not been established. There is insufficient evidence on the short term and long term benefit of gastric pacing for obesity and therefore, is considered investigational.


Based on the peer reviewed medical literature gastric electrical stimulation (GES) may be safe and effective option for those patients with intractable nausea and vomiting secondary to gastroparesis who have failed all other treatments. The use of GES or gastric pacing of the treatment of all other indications remains unproven, optimal patient selection criteria, electrode position, lead number and stimulation patterns have not yet been determined. Additional well designed studies are not needed to demonstrate the safety and effectiveness of GES for these indications.


Practice Guidelines and Position Statements
The American College of Gastroenterology

The American College of Gastroenterology published a clinical practice guideline  on the management of gastroparesis in 2013. The recommendations for these guidelines were based on review of the evidence base through 2011. The evidence on GES consisted of 2 randomized crossover trials and the case series. The recommendation for GES was that “Gastric electrical stimulation may be considered for compassionate treatment in patients with refractory symptoms, particularly nausea and vomiting. Symptom severity and gastric emptying have been shown to improve in patients with diabetic gastroporesis (DG), but not in patients with idiopathic gastroparesis (IG) or postsurgical gastroparesis (PSG). (Conditional recommendation (there is uncertainty about trade-offs), moderate level of evidence (further research would be likely to have an impact on the confidence in the estimate of effect)


National Institute for Health and Care Excellence (NICE)
In 2014, the National Institute for Health and Care Excellence issued guidelines on    gastroelectrical stimulation for gastroparesis that made the following recommendation:

  • Current evidence on the efficacy and safety of gastric electrical stimulation for gastroparesis is adequate to support the use of this procedure with normal arrangements for clinical governance, consent and audit.
  • During the consent process, clinicians should inform patients considering gastric electrical stimulation for gastroparesis that some patients do not get any benefit from it. They should also give patients detailed written information about the risk of complications, which can be serious, including the need to remove the device.
  • Patient selection and follow up should be done in specialist gastroenterology units with expertise in gastrointestinal motility disorders, and the procedure should only be performed by surgeons working in these units.
  • Further publications providing data about the effects of the procedure on symptoms in the long term and on device durability would be useful. 

Regulatory Status
The Enterra™ Therapy System received FDA approval through a humanitarian device exemption. This regulatory category was established in 1996 and only applies to devices intended to benefit fewer than 4,000 patients. The approval phase is similar to that of a premarket approval application (PMA) but is exempt from the effectiveness requirements of a PMA. The application is not required to include results of scientifically valid clinical investigations but must contain sufficient information for the FDA to determine that the device does not post unreasonable or significant risk of illness or injury. A humanitarian use device may only be used in facilities that have an institutional review board (IRB) to supervise clinical testing of the device.   

Prior Approval:

Not applicable.



See also Humanitarian Use Devices medical policy 10.01.14

See also Vagus Nerve Stimulation (VNS) medical policy 07.01.60


Gastric electrical stimulation (eg, Enterra™ Therapy) may be considered medically necessary and, therefore, covered for the following humanitarian device exemption (HDE) indication granted by the US Food and Drug Administration (FDA):

  • For the treatment of chronic, intractable nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology refractory to medical management. 

An institutional review board (IRB) must approve the use of gastric electrical stimulation for the treatment of gastroparesis to ensure that it will be used in accordance with the HDE indication(s) granted by the FDA.  Documentation of IRB approval may be requested to ensure compliance with such indications.


FDA-labeled HDE indication(s)External Site


Gastric electrical stimulation and gastric pacing would be considered investigational for all other indications, including but not limited to the following because the safety and effectiveness of this service cannot be established by review of the available published medical literature:

  • As an initial treatment for gastroparesis
  • For treatment of diabetes mellitus in persons without gastroparesis
  • For the treatment of gastrointestinal dysmotility disorders other than gastroparesis as indicated above
  • For the treatment of obesity

Procedure Codes and Billing Guidelines:

  • To report provider services, use appropriate CPT* codes, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.
  • 43647 Laparoscopy, surgical; implantation or replacement of gastric neurostimulator electrodes, antrum
  • 43648 revision or removal of gastric neurostimulator electrodes, antrum
  • 43659 Unlisted laparoscopy procedure, stomach (if used to report laparoscopic procedures related to gastric electrical stimulation electrode placement)
  • 43881 Implantation or replacement of gastric neurostimulator electrodes, antrum, open
  • 43882 Revision or removal of gastric neurostimulator electrodes, antrum, open
  • 43999Unlisted procedure, stomach (if used to report laparotomy procedure related to gastric electrical stimulation electrodes placement)
  • 64590 Insertion or replacement of peripheral or gastric neurostimulator pulse generator or receiver, direct or inductive coupling.
  • 64595 Revision or removal of peripheral or gastric neurostimulator pulse generator or receiver. 
  • 95980 Electronic analysis of implanted neurostimulator pulse generator system (eg, rate, pulse amplitude and duration, configuration of wave form, battery status, electrode selectability, output modulation, cycling, impedence and patient measurements) gastric neurstimulator pulse generator/transmitter; intraoperative, with programming.
  • 95981 subsequent, without programming
  • 95982 subsequent with reprogramming
  • C1767 Generator, neurostimulator (implantable), nonrechargeable
  • C1778 Lead, neurostimulator
  • C1787 Patient programmer, neurostimulator
  • C1816 Receiver and/or transmitter neurostimulator (implantable)
  • C1820 Generator, neurostimulator (implantable), non high-frequency with rechargeable battery and charging system
  • C1822 Generator, neurostimulator (implantable), high frequency, with rechargeable battery and charging system
  • C1897 Lead neurostimulator test kit (implantable)
  • L8679 Implantable neurostimulator, pulse generator any type
  • L8680 Implantable neurostimulator electrode, each
  • L8681 Patient programmer (external) for use with implantable programmable neurostimulator pulse generator, replacement only
  • L8682 Implantable neurostimulator radiofrequency receiver
  • L8683 Radiofrequency transmitter (external) for use with implantable neurostimulator radiofrequency receiver
  • L8685 Implantable neurostimulator pulse generator, single array, rechargeable, includes extension
  • L8686 Implantable neurostimulator pulse generator, single array, nonrechargeable, includes extension
  • L8687 Implantable neurostimulator pulse generator, dual array, rechargeable, includes extension
  • L8688 Implantable neurostimulator pulse generator, dual array, nonrechargeable, includes extension
  • L8689 External recharging system for battery, (internal) for use with implantable neurostimulator, replacement only

Selected References:

Wellmark's policy is based on:

  • National Institute of Clinical Excellence (NICE). Gastroelectrical Stimulation for Gastroparesis. December 2004.
  • 2013 Clinical Guideline: Management of Gastroparesis. The American College of Gastroenterology. Michael Camilleri, M.D., Henry P. Parkman, M.D., Mehnaz A. Shafti, M.D., Thomas L. Abell, M.D. and Laruen Gerson, M.D., MSc. AmJGastroenterolExternal Site 2013; 108:18-37;doi:10.1038/ajg.2012.373.
  • UpToDateExternal Site Treatment of Gastroparesis. Michael Camilleri, M.D.. July 17, 2013.
  • UpToDateExternal Site Electrical Stimulation for Gastroparesis. William L. Hasler, M.D. August 20, 2012.
  • ECRI. Product Brief. Enterra Therapy System (Medtronic, Inc) for Treating Gastroparesis. July 2013.
  • Information Sheet Guidance for IRBs, Clinical Investigators, and Sponsors, Frequently Asked Questions About Medical Devices
  • HDE ApprovalsExternal Site Listing of CDRH Humanitarian Device Exemptions
  • Soffer Edy E. Gastric Electrical Stimulation for GastroparesisExternal Site J Neurogastroenterol Motil, Vol. 18 No. 2 April 2012
  • National Institute for Clinical Excellence (NICE). Interventional Procedures Guidance (IPG489)External Site Published May 2014. Gastroelectrical Stimulation for Gastroparesis.
  • UpToDateExternal Site  Electrical Stimulation for Gastroparesis. William L. Hasler, M.D., Topic last updated September 16, 2015.
  • UpToDateExternal Site  Treatment of Gastroparesis, Michael Camilleri, M.D., Topic last updated July 7, 2015.
  • UpToDateExternal Site  Malignancy Associated Gastroparesis: Pathophysiology and Management, Mehnaz A Shafi, M.D., Eiad Nasser, M.D., Milind Javle, M.D., Topic last updated August 10, 2015.
  • Abell Thomas, McCallum Richard, et. al. Gastric Electrical Stimulation for Medically Refractory Gastroparesis, Gastroenterology 2003;125:421-428
  • Lin Zhiye, Forster Jameson, et. al. Treatment of Diabetic Gastroparesis by High Frequency Gastric Electrical Stimulation, Diabetes Care Volume 27, Number 5, May 2004
  • Greenway Frank, Zheng Jolene, Electrical Stimulation as Treatment for Obesity and Diabetes, Journal of Diabetes Science and Technology, Volume 1, Issue 2 March 2007
  • Naga Venkatesh G. Jayanthi, Simon P.L. Dexter, Gastric Electrical Stimulation for Treatment of Clinically Severe GastroparesisExternal Site Journal of Minimal Access Surgery, January 2013
  • Cha Ryan, Marescaux Jacques, et. al. Updates on Gastric Electical Stimulation to Treat Obesity: Systematic Review and Future Perspectives, World Journal of Gastrointestinal Endoscopy Sept 2014; 6(9):419-431

Policy History:

  • October 2015 - Annual Review, Policy Revised
  • February 2015 - Policy Revised
  • November 2014 - Annual Review, Policy Revised
  • January 2014 - New Policy Created

Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc.   They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.

*Current Procedural Terminology © 2012 American Medical Association. All Rights Reserved.